Apparatus for shelling and de-germinating corn

ABSTRACT

The apparatus comprises a stator (1) and a rotor (3) rotatably supported in a stator housing (2) with a processing space (9) therebetween. The stator housing (2) and rotor (3) are fitted with knobs on their mutually facing sides in the region of the processing space (9) where the corn is processed. Work elements (8, 13, 21) with knobs are positioned in approximation of a circle at the stator housing (2) and at the rotor (3). The inside of the stator housing is divided in the cirucmferential direction into siftings segments (21, 22) with sieve holes provided in an alternating manner with knob segments. The stator housing (2) includes at least two detachable housing wall parts (14, 15) making the processing space (9) easily accessible in the event of operational disturbance therein.

BACKGROUND OF THE INVENTION

The present invention is directed to an apparatus for shelling anddegerminating corn.

At the present time, corn is processed in large quantities to form thegreatest variety of end products. In addition to the wet de-germinatingof the corn for starch production, the corn is de-germinated and groundfor conventional uses in milling. The end products of the processing inthe mill are substantially supplied to the feedstuff and oil industries,the brewing industry, polenta production, the snack product industry orcorn flake production. Each of these uses places different demands onthe processing in the mill, wherein the investment and processing costsfor the processing in the mill increase in the sequence of intended usesnamed above.

The apparatus, according to the invention, is used for the production offlaking grits which constitute the starting product for corn flakeproduction. The demands placed upon milling are the highest in thisinstance. The de-germinating and shelling of corn for this purpose havebeen effected for decades in the "Beall de-germinator". The lattercomprises a stator, a rotor being rotatably supported in the statorhousing. The stator housing and the rotor form a processing space whichis at least approximately annular in cross section and have knobs ontheir mutually facing sides. In addition, the inside of the stator isdivided into siftings segments in the circumferential direction, whichsiftings segments are provided alternately with knobs or with a sievehole, respectively. This known apparatus also comprises a stator housinghaving two parts, whose two halves are separated by a horizontal planeand are swivelable relative to one another around a hinge axis and canbe screwed together in the closed state. If the upper half of the statorhousing is removed (folded up), the lower half forms a trough, which isshaped like a half-circle in cross section, the rotor which is held inbearing half-shells at the ends lies in the trough. By means of foldingup the upper stator housing half, the lower half of the processing spaceis not accessible. The rotor must also be removed for this purpose. Inaddition, the Beall de-germinator comprises a conical work space whichincreases in diameter from the inlet end to the discharge end, and thestator housing and rotor are constructed conically in a correspondingmanner. If the work space is to be changed in the direction of the rotorradius corresponding to the nature of the corn to be processed, therotor is axially displaced in the stator housing. This requires acomparatively costly bearing support. If it is necessary to build suchmachines for greater outputs with longer processing spaces, the diameterof the rotor and stator housing must be correspondingly enlarged towardthe discharge end, as well. Another disadvantage of this apparatus isthe fact that the corn dust portion in the flaking grits is high, whichdetracts from the yield.

SUMMARY OF THE INVENTION

The object of the present invention is to improve an apparatus of thetype described above in such a way that the processing space is easilyaccessible in the event of disturbance and the shelling andde-germinating process can be managed in an optimal manner.

Blockage in the processing space can be corrected by means of thedetachable housing wall parts when the machine is running. Inparticular, the cross section of the processing space can be adapted tothe nature of the material to be processed without an axial displacementof the rotor.

When the processing space, which is annular in cross section, has thesame or at least approximately the same diameter along its entirelength, its length can be increased without the machine taking up morespace in width or height. In addition, the occurrence of dust in thedischarge is greatly reduced by means of this step and the requiredpower is lower while maintaining the same product throughput. Theadvantage of the lower portion of dust in the discharge is that thelatter need not be fed to the additional sifters jointly with thesiftings, as was previously the case. The cost for the subsequentsifting is accordingly reduced. A further advantage results in that theoutput can be doubled with half the power requirement while maintainingthe same rotor length as in the Beall de-germinator and with the samework quality.

In the apparatus, according to the invention, the processing space canbe opened in the event of disturbance in an effortless manner along acircumferential angle of approximately 270° and the disturbance can beeliminated.

It is possible to adjust different radial spacing of the adjustable knobsegments in the end areas of the processing space and accordingly toadjust the manner of operation of the apparatus in an optimal fashion.

The knob segments, which are exposed to considerable wear, can beexchanged on the side of the stator as well as on the side of the rotorwithout needing to exchange the rotor. The down times of the machine andthe maintenance costs are accordingly greatly reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is explained by way of example by means of the attachedschematic drawing.

FIG. 1 shows a side view of an apparatus, wherein parts of the statorhousing are omitted;

FIG. 2 shows a section along line II--II in FIG. 1;

FIGS. 3 and 4 show a section from FIG. 2;

FIG. 5 shows a side view of a second embodiment example of an apparatusin accordance with the invention;

FIG. 6 shows a diagram of a corn processing system and;

FIGS. 7 to 11 show views, corresponding to FIG. 3, of additionalembodiments in accordance with the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The stator 1 of the apparatus shown in FIGS. 1 and 2 comprises a statorhousing 2 which encloses a rotor 3, the rotor 3 being supported thereinso as to be rotatable, and is mounted on the horizontal supporting frame5 of a stand 4 and opens at the bottom into an adjoining funnel 6. Thesiftings are guided through the latter. A longitudinal support 7 bridgesthe frame 5 in the longitudinal direction, a knob segment 8 comprisingknobs (spikes) directed against the processing space 9 being fastenedthereon. The stator housing 2 is closed at the ends by means of a frontplate 10 and plate 11 whose upper sides are connected and strengthenedby means of a longitudinal support 12. The latter supports an additionalknob segment 13 whose knobs, which are directed into the processingspace 9, lie diametrically opposite those of the knob segment 8. Inaddition, the support 12 is provided with two adjustable aspiratingslots A so that the space for the siftings can be sufficientlyventilated. The screw connection between the longitudinal support 12 andthe knob segment 13 can be effected by means of adjusting screws withwhich the radial distance of the knob segment 13 from the rotor 3 can beadjusted.

Further, there are two detachable housing wall parts 14 and 15 of thestator housing 2 between the two front plates 10 and 11 and at oppositesides of the longitudinal supports 7 and 12. Angle sections 16, whichare screwed to the front plates 10 and 11, respectively, are located atthe ends of these housing wall parts 14 and 15. The housing wall parts14 and 15 adjoin the two front plates 10 and 11 with end plates 17 whichare securely connected with one another by means of two angle sectionstrips 18 and 19 and a U-section support 20. Another knob segment 21 isscrewed into each U-section support 20. In addition, a siftings segment22 in the form of a perforated plate is fastened between the U-sectionsupport 20 on one side and the angle section strips on the other side.The angle section strips 18, 19, the U-section support 20 comprising theknob segment 21, and the end plates 17 form a constructional unit. Thelatter, together with the angle sections 16, form a housing wall part 14or 15 with which they are connected at the ends by means of an adjustingscrew 23 in each instance. When the adjusting screw 23 is turned, forwhich purpose the manual expenditure of force is slight, the entireconstructional unit is displaced toward the longitudinal central axis ofthe processing space or away from the latter. If the screw connectionbetween the angle section strips 16 and the contacting front plates 10,11 is loosened, the two housing wall parts 14, 15, i.e. theconstructional unit 17 to 21, including the angle section strips 16, canbe removed to the side, and the processing space 9 with the rotor 3 canbe opened to a great extent.

A hollow section with axle stubs 25 at the ends, which hollow section isoctagonal in cross section, forms the core 24 of the rotor 3. It issupported along with the latter in pivot bearings of the stator housing2 so as to be drivable. Knob plates 26, which are like circle segmentsin cross section, are screwed on along the length of the core 24 on itsplane portions so as to be detachable. These knob plates 26 areoutfitted with knobs in a spiked manner, wherein the knobs are arrangedor structured in the shape of a helix in the inlet area (FIG. 1, atleft).

The enveloping surface of the rotor 3 is a cylinder jacket. Theprocessing space 9 has an approximately annular cylindrical shape incross section in a corresponding manner. The relative speed between theknobs on the stator side and on the rotor side is therefore uniformalong the entire length of the processing space. However, the envelopingsurface can also be slightly conical without the advantages of theinvention as a whole being jeopardized. As shown in FIG. 3, the width ofthe processing space 9 can be changed by means of turning the adjustingscrews 23 in the radial direction in that the oppositely located knobplates 21 of the two housing wall parts 14, 15 with the adjoiningsiftings segments 22 are displaced toward the rotor 3 or away from it,respectively. According to the intended use, the width of the processingspace 9 in the inlet area can be set so as to be larger or smaller thanin the discharge area by means of adjusting the adjusting screws 23. Theshape of the processing space 9 is therefore adaptable in an optimalmanner to the quality of the type of corn to be processed.

The corn to be processed is poured into the processing space 9 throughan inlet connection piece 27 in the stator housing 2. The corn is drawninto the processing space by means of the helically structured surfaceof the rotor in the inlet area, crushed between the knobs and pressedagainst the farther end, where the endosperm portions making up thetailings arrive in a chamber 28 between the rotor 3 and the front plate-1. The front plate 11 is penetrated by an outlet opening 29 throughwhich the tailings fall into a discharge funnel 30 and which opening canbe closed by means of a flap 31. The closing force of the latter isadjustable by means of an adjusting weight 32 which can be displaced ona balance arm 33 which is securely connected with the flap 31. Thethroughput time of the endosperm portions through the processing space 9is influenced by the position of the adjusting weight 32.

During the crushing of the corn in the processing space 9, shells,sprouts and endosperm portions are separated and the detached shells,sprouts and a small portion of the endosperm parts fall through thesiftings segment 22 into the funnel 6. The larger endosperm portionsmigrate through the processing zone 9 and pass through the outletopening 29 into the discharge funnel 30 as tailings.

Should blockage occur in the processing space 9 in the operating stateof the machine, it can be eliminated in that the knob segment 21 withthe adjoining siftings segments 22 is moved radially outward on one sideby means of turning the adjusting screws 23 until the blockage isloosened. The knob segment is then brought back into its workingposition.

Because of the friction process taking place in the processing space,both the knob plates 26 and the knob segments 8, 13 and 21 are exposedto considerable wear. If the knob plates 26 at the rotor 3 are to bereplaced, it is only necessary to remove one of the two housing wallparts 14 or 15 completely after loosening the screw connections 34. Oneknob plate 26 after the other can then be detached at the rotor andreplaced. If the four knob segments 8, 13 and 21 are to be replaced,both wall parts 14 and 15 are removed in the described manner afterloosening the screw connections 34 and the worn knob segments areexchanged.

The output is doubled accompanied by the lowest constructional cost andspace requirement in the embodiment form according to FIG. 5. In thiscase, both the stator and the rotor are symmetrical with respect to avertical plane of symmetry in which the inlet connection piece 27 iscentrally located, the plane of symmetry being at a right angle to therotor axis. The product intake is effected by means of a helicalstructure at the rotor 3 in the inlet area, which helical structureresults from the symmetry and the product is directed in the oppositedirections. The discharge of the larger endosperm portions is likewiseeffected at the two ends of the rotor housing in corresponding dischargefunnels 30 and 30'.

The corn material fed through the inlet connection piece 27 is dividedup in the processing space and diverted into two opposite directions. Inboth directions, the corn is subjected to the safe treatment and thesiftings are caught correspondingly in two separate funnels 6, 6' andguided together again for further processing. The tailings dischargedfrom the funnels 30 and 30', i.e. the larger endosperm portions, arealso combined for further processing.

FIG. 6 shows a production system for flaking grits in which an apparatus35, according to the invention, is integrated for shelling andde-germinating the corn. After the special units 36 for preparing thecorn by means of water and/or steam, the corn arrives in the apparatus35, according to the invention. Because the tailings are free of mealand shells, they can be fed directly to a plansifter 38 via a cyclone37. It is not necessary to combine the tailings with the siftings, as isrequired when using the known devices (because of the meal and shellportion of up to 7% in the tailings). The siftings arrive in a turbinesifter 41 via additional cyclones 39 and 40, which turbine sifter 41separates out the endosperm portions contained in the siftings and feedsthem to a second plansifter 43 via a scale device 42. The cleaning pathfor the siftings, which comprises a turbine sifter and is more costly interms of construction, can be dimensioned so as to be smaller andtherefore less expensive, since it is no longer loaded by the tailingsas was previously the case.

In the embodiments according to FIGS. 7 to 11, the same referencenumbers designate the same parts as in the according to FIGS. 1 to 5.The embodiment according to FIG. 7 differs from the latter in that theradial distance between the siftings segments 22 on the one side and therotor 3 on the other side of the processing space 9 is likewiseadjustable. For this purpose, the siftings segments 22 are reinforced atthe end by means of flange plates 36 which are penetrated by a slottedhole 37. These flange plates 36 lie against the end plates 17. Inaddition, the area of the siftings segment 22 adjoining the sectionstrip 18 is bent back in an outward direction so that it forms anabutment surface 38 against the latter. The flange plate 36 can bescrewed securely to the end plate by means of a screw 39 which is guidedthrough the slotted hole 37, and in addition it overlaps the other endarea of the siftings segment 22 with a bent portion 40, which end areais bent outward. This bent portion 40 and the siftings segment 22 areprovided with a slotted hole 41 through which a threaded shaft 42engages which fits securely in the leg of the U-section support 20. Theflange plate 36 is securely connected with the U-section support 20 bymeans of tightening a nut 43 on the threaded shaft 42. In order toadjust the radial distance of the siftings segment 22 from the rotor 3it is necessary only to loosen the screws 39 and the nuts 40 and todisplace the siftings segment.

In the embodiment of FIG. 8, the stator housing 2 is constructed in thesame manner as in FIG. 7. The design of the core 3 is different. A knobplate 26 is attached only on every second plane portion of the core 24which is octagonal in cross section, rather than on every plane portion.The portions lying between the latter are equipped with a plane blankplate 24. The embodiment of FIG. 9 differs from that according to FIG. 7in that the siftings segments 22 are not bent parallel to the envelopingjacket of the rotor 3, but, rather, are planar.

In the embodiment of FIG. 10, the knob segments are absent on the sideof the stator (in contrast to the preceding examples). The knob segments8 and 13 are replaced with blank plates 45 and the knob segments 21 arereplaced by siftings segments 46. In addition, the processing space 9has an octagonal annular cross section.

In the embodiment of FIG. 11, the knob segments 8 and 13 of the statorhousing are present, whereas; the knob segments 21 are replaced by thesiftings segments 22.

I claim:
 1. An apparatus for de-germinating corn comprising:a statorhousing including a fixed wall part and at least two detachable wallparts; a rotor positioned in said stator housing rotatably supported insaid stator housing for rotation about an axis, a processing spaceexisting between said stator housing and said rotor and said rotorincluding knobs facing said processing space; said stator housingincluding sifting segments partially defining said processing space,said two detachable wall parts each having at least one knob and bothbeing radially adjustable with respect to the axis of rotation of saidrotor.
 2. Apparatus as claimed in claim 1, wherein said rotor has agenerally uniform diameter.
 3. Apparatus as claimed in claim 1, whereinsaid stator housing further includes knob segments including knobspositioned between said sifting segments in an alternating manner, saidknob segments of said stator housing and said sifting segments facingsaid processing space, and means for supporting and adjusting at leastone of said knob segments at said stator housing, said at least one knobsegment being radially adjustable relative to the axis of rotation ofsaid rotor.
 4. An apparatus as claimed in claim 1, wherein said twodetachable wall parts are symmetrical with respect to an imaginary planecontaining said axis of rotation of said rotor.
 5. An apparatus asclaimed in claim 1, further comprising an adjusting means for adjustingsaid detachable wall parts having said at least one knob segment, saidadjusting means being positioned at the outside of said stator housing.6. An apparatus as claimed in claim 5, wherein said adjusting means isarranged in the end regions of said processing space.
 7. An apparatus asclaimed in claim 4, wherein said plane is oriented at right angles to ahorizontal plane.
 8. An apparatus as claimed in claim 1, wherein saidstator housing is divided into four housing sectors, and two of saidhousing sectors form said detachable housing wall parts.
 9. An apparatusas claimed in claim 8, wherein said housing sectors forming said twodetachable housing wall parts include two said sifting segments and aknob segment facing said processing space.
 10. An apparatus as claimedin claim 8, further comprising supporting means for holding said statorhousing n position during operation of said apparatus and wherein two ofsaid housing sectors lies opposite one another, and further comprisingmeans for securely connecting said two of said housing sectors with saidsupporting means.
 11. An apparatus as claimed in claim 10, wherein saidhousing sectors which are securely connected with said supporting meansinclude a knob segment facing said processing space in each instance.12. An apparatus as claimed in claim 11, wherein at least one of saidknob segments of one of said housing sectors is axially adjustablerelative to the rotational axis of said rotor.
 13. An apparatus asclaimed in claim 1, wherein said rotor includes a core forming a uniformpolygon in cross section and an envelope surface, knob plates with knobsand having the shape of a circle segment in cross section beingdetachably fastened at said core.
 14. An apparatus as claimed in claim13, wherein said knob plates extend in one piece along the entire lengthof said processing space.
 15. An apparatus as claimed in claim 14,wherein said processing space has an inlet region and a discharge regionand said knob plates include one of helically extending knobs and ribsin said inlet region of the processing space.
 16. An apparatus asclaimed in claim 13, wherein the envelope surface of said rotor is acylindrical surface.
 17. An apparatus as claimed in claim 13, whereinsaid processing space has an inlet end and a discharge end, the envelopesurface of the said rotor is a conical surface which tapers toward oneof said inlet end and said discharge end of said processing space. 18.An apparatus as claimed in claim 1, wherein said stator housingcomprises a discharge opening at each end of said processing space andan inlet opening therbetween, said rotor and said stator housing beingsymmetrical to a plane intersecting said rotor axis at a right angle inthe region of said inlet opening.
 19. An apparatus as claimed in claim1, wherein the radial distance between said sifting segments and saidrotor is adjustable.
 20. An apparatus as claimed in claim 1, whereinsaid detachable housing wall parts are constructed as sifting segments.